Alfred swan



(No Model.)

A. SWAN. INGA NDBSGENT ELECTRIC LAMP SOCKET. No. 439,367.

Patented Oat. 28, 1890.

UNITE STATES PATENT. OFFICE.

ALFRED SWAN, OF ORANGE, NEW JERSEY, ASSIGNOR TO THE INSULITE MANUFACTURING COMPANY, OF NEW YORK, N. Y.

INCANDESCENT ELECTRIC- LAM P SOCKET.

SPECIFICATION forming part of Letters Patent Ne. 439,367, dated October 28,1890.

Original application filed March 5,1889, Serial No. 301,841. Divided and this application filed July 23, 1890. Serial No.

359,641. (No model.) Patented in England March 28, 1889, No. 5,066.

To all whom it may concern.-

Be it known that I, ALFRED SWAN, a subject of the Queen of Great Britain, residing at Orange, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Electric Lamps, fully described and represented in the followin g specification, and the accompanying drawings forming a part of the same, the said improvements being embraced in British Letters Patent No. 5,066, dated March 23, 1889.

This invention relates to improvements in sockets 0r holders for incandescent electric lamps, it being the object of the invention to provide a holder for this class of lamps which shall be much more simple and inexpensive than those heretofore in use, and which shall provide a more perfect insulation and protection for the conductors.

A full understanding of the invention can best be given by anillustration and a detailed description of a lamp-holder embodying the same, and all preliminary description will therefore be omitted and a detailed description given, reference being had to the accompanying drawings, in which- Figure 1 is a sectional elevation of an ordinary form of incandescentelectric lamp, showing the same attached to a socket or holder constructed according to the present invention. Fig. 2 is a cross-section of the holder, taken upon the line 2 of Fig. 1. Fig. 3 is a view similar to Fig. 1, showing a slight modification, which will be hereinafter referred to. V

Referring to said figures, it is to be understood that A represents an incandescent elec tric lamp of ordinary form, the carbon filament at being connected to wires 2, one of which is connected to a metal contact-plate 4 set into the cement at the baseof the lamp, while the other is connected to a metal band 5, which surrounds the base of the lamp, all in substantially the usual way. The metal band 5 is screw-threaded upon its exterior, and is adapted to be screwed into a threaded socket 6, formed in the base of the holder in such manner that when the lamp is in position in the holder the contact-plate 4 will form electrical contact with one of the wires of the circuit, while the metallic ring 5 will form contact with the other wire of the circuit.

The holder Bis of any suitable form, preferably round in cross-section, and tapering to ward its top, so as to be approximately the form of a truncated cone. The base or body of this holder is formed, preferably, of a plastic material or compositionsuch, for example, as papier-machwhich can readily be molded into suitable form, and which is a nonconductor of electricity, and which I shall refer to as an insulating material. The holder, formed of this material and molded in this manner, is provided with ducts or passages 7 8 for receiving two line-wires 9 10, forming the electric circuit for the lamp, the duct 7 leading from the top of the holder to the socket 6 in such manner that the terminal of the wire 9 can form contact with the plate 4, while the duct 8 also leads from the top of the holder to such a point as to permit the terminal of the wire 10 to form contact either directly or indirectly with the metallic band 5 of the lamp. For the purpose of forming a suitable terminal for the wire 9 to form contact with the plate 4, the base of the socket 6 is provided with a recess into which is set a small socket 12, having an opening in its bottom which communicates with the duct 7, and through which the wire 9 is introduced into the socket. The socket. 12 is screwthreaded upon its interior, and receives a screw-plug 13, which is arranged to be screwed into the socket so as to bind the end of the wire 9 between the socket and the plug. When the lamp is screwed into the socket 6, the plate 4 forms contact with the plug 13, and thus connects one of the wires 2 of the lamp with the wire 9 of the circuit.

In the construction illustrated in Figs. 1 and 2 the socket 6 receives a metal thimble or collar 14, which is screw-threaded upon its interior to receive the band 5. This thimble is provided upon its upper edge with an extension 15, which is embedded in the material of the holder and terminates in a plate 16, located in a laterally-opening recess 17 in the side of the holder, which recess communicates with the duct 8, so that the terminal of the wire 10 can be secured to the plate 16 by a binding-screw 18, thus forming the metallic connection between the wire 10 and the other wire 2 of the lamp.

As illustrated in Fig. 1, the holder is designed for a hanging lamp, and is therefore arranged to be suspended from the cable formed of the wires 9 10. In order to support the holder and the lamp, the holder is provided at its top with a metallic cap 19, having an opening. for the passage of the wires 9 10, and the wires are knotted, as shown, just below the cap, so that the weight of the holder and lamp is sustained by the cap which rests upon the knot, and thus relieves the terminals of strain. If the holder is to be used for a chandelier or a rigid lamp instead of a hanging lamp, the holder may be screwed onto the end of a tube or other rigid support. If it is desired to give a more finished appearance to the holder, the cap 19 may be extended so as to cover the screw 18 and the greater part of or cover the entire holder, or the holder may be cast into the sheath thus formed. If it is desired to construct the holder so as to adapt it for supporting a shade as well as a lamp, the thimble 14 can be screw-threaded upon its exterior, so as to receive a threaded ring 20 for supporting an ordinary shade C, as indicated in Fig. 1, the shade being provided with a central opening by which it is passed over the thimble to the proper position, after which the ring 20 is screwed onto the lower end of the thimble to hold the shade in position before the lamp is introduced into the socket.

In some'cases it may be desirable to dis pense with the metallic thimble 14, and this can readily be done by forming the threads for the interior of the socket 6 in the material of the holder, as indicated in Fig. 3. In such case the binding-screw 18 will be so lo cated that after the lamp has been screwed into the socket so that the plate 4 forms contact with the plug 13 the screw 18 can be set up so as to abut against the band 3, and thus complete the circuit through the lamp, and at the same time looking the lamp in position in the socket. In this case the plate 16 is provided with a countersink to receive the head of the screw 18, so as to permit the screw to be advanced slightly-varying distances to insure reliable contact both with the wire and the band 5. In this case the shade C may be secured to the holder by set-screws 25,which enter: a recess 26 formed upon the outside of the holder, as also shown in Fig.3.

In the construction shown in Fig. 1 the thimble 14:, as will be observed, projects below the insulating material of the holder so as to be exposed, and as this thimble forms the terminal of one of the wires of the circuit this exposure of the thimble is to some extent objectionable, because of the liability of making connection with the thimble accidentally in handling the holder when the lamp is de tached, and thus diverting the current. This objection is largely overcome in the construction shown in Fig. 3, in which the thimble is omitted, and the terminals of both wires of the circuit substantially inclosed within the holder and concealed.

This application is a division of my application No. 301,841, filed March 5, 1889, in which is claimed a socket molded from plastic material, and of which my applications No. 301,842, filed March 5, 1889, and No. 308,056, filed April 22, 1889, are also to be considered divisions.

What I claim is 1. The combination, with an incandescent electric lamp and its holder, of a socket 12, set into the holder and receiving the end of one of the line-wires, and the plug 13, adapted to be screwed into the socket 12 to bind the wire and to form contact with the base of the lamp, substantially as described.

2. In an incandescent-electric-lamp holder, the combination, with the base or body formed of insulating material and provided with a screw-threaded metallic socket for receiving a line-wire, of a screw-plug clamping the line-wire against the socket and forming a contact for the lamp, substantially as described.

3. In an incandescent-electric-lamp holder, the combination, with the base or body formed of insulating material and provided with a metallic socket for receiving a line-wire, of a plug clamping the line-Wire against the socket and forming a contact for the lamp, substan tially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

ALFRED SWVAN. lVitnesses:

W. ARTHUR,

GEORGE F. GIERING. 

